Is bigger always better? When it comes to brain size, that has long been the prevailing theory—at least among big-brained humans. But a new analysis shows that in the course of primate evolution, brains and brawn haven't always been on the rise.

Ever since a petite female Homo floresiensis (or "hobbit") was described in 2004, scientists have been debating whether this recently extinct hominin could have evolved to have such a small noggin or if this specimen—the only one for which a skull has been found—was an aberration.

The Indonesian individual stood at just about one meter high and had a brain about a third the size of modern humans. Despite these striking size differences, some H. floresiensis fossils date to just 13,000 years ago—which means they would have lived alongside brainy humans for some 187,000 years. Some researchers propose that she and her clan were modern descendents of Homo erectus and had devolved to their diminutive stature because they lived on an island (a phenomenon documented in other species known as insular dwarfism) or that her particular errant body and brain size were due to an underlying pathology, such as dwarfism or an oversized pituitary gland.

Others, however, posit that H. floresiensis is from a more primitive lineage and evolved—for whatever reason—to have this smaller brain.

A new study, published online January 26 in the journal BMC Biology, brings some new perspectives to the table, examining size trends in primate evolution and finding that brains and bodies don't always get bigger over time.

Tuesday, January 26, 2010

University of Tennessee College of Veterinary Medicine staffers have performed surgery on Binti, a 25-year-old female chimpanzee at the Knoxville Zoo, to stabilize four broken metacarpal bones in her hand.

Earlier this week, zookeepers observed Binti holding a swollen hand close to her body. Radiographs revealed four broken metacarpal bones between her knuckle and wrist.

University of Tennessee veterinarians placed four metal plates in her hand to stabilize the broken bones and allow them to heal.

After the procedure, Binti returned to Knoxville Zoo to begin her recovery; zoo officials say she'll need plenty of rest and quiet for the next two weeks.

Monday, January 25, 2010

A monkey that escaped its enclosure at Ueno Zoo in Tokyo was finally cornered in the basement of a restaurant in a neighboring park.

The Japanese macaque was one of 23 released into the zoo's monkey enclosure on Jan. 24 at around 9.30 a.m. As soon it was released, it scaled the enclosure's 4.5-meter concrete wall and escaped outside the zoo.

It was found at around 4 p.m. later that day, in the stairway leading to the basement of Sakuragitei restaurant in Ueno Park, located several hundred meters away from the zoo.

"I saw this black thing dashing away, and I thought it had to be the escaped monkey. It calmed down after it was caught," said the restaurant worker who discovered the monkey.

Following its recapture, it was returned to the zoo and placed in an individual enclosure away from the general public.

Researchers have proved that they are able to calculate in their heads whether the number of dots on a screen is increasing or decreasing.

They can then make a decision based on that finding, the experiment found.

Professor Andreas Nieder, who led the study at the University of Tubingen, Germany, believes the finding suggest that basic mathematics is "hard-wired into evolution".

"It is a primitive version of maths which we think has a survival advantage," he said. "If you are foraging then it is an advantage to choose a tree with more berries on it.

"Similarly it is important that a monkey knows the number of individuals in his or her social group and compares it with rival groups. To know whether to attack or retreat."

The study, published in the Proceedings of the National Academy of Sciences, involved training monkeys to recognise the number of dots on a screen flashed before them and compare them with subsequent sets of dots shown to them later.

If a red light was flashed before them later, then they had to pull a lever if there were more dots in the second image and if a blue circle flashed before them then the lever had to be pulled if it contained less dots.

The monkeys, who were given apples or water as a reward, made the correct decision up to 90 per cent of the time.

Friday, January 15, 2010

The University of Washington's National Primate Research Center is under scrutiny after it admits to allowing a monkey to starve to death.

A 3 1/2-year-old pigtailed macaque was found dead inside of its cage back in April. The likely cause of death was starvation.

The monkey had lost 25 percent of its body weight, and they typically only weigh between 12 and 24 pounds.

"As with any activity that's based on human behavior, occasionally mistakes will occur," said David Anderson, Director, National Primate Research Center.

Anderson says the monkey was housed at the research center with 15 other macaques. It appeared to have a healthy coat and was social with the others.

It's common for the monkeys to conceal sickness - a trait from the wild.

"Even though they're bred for research they maintain some of their behaviors in the wild and one of those is to hide any ill health or infirmity because obviously that would make them more susceptible to predation," said Anderson.

But the staff is required to weigh the animals every four weeks. In this case two months had gone by.

The problem? A change in staff and confusion over who was responsible.

This is not the first time UW's program has been under a microscope. There have been other incidents, including five baboons that died of thirst in 1995 at a breeding center near Spokane.

Department of Natural Resources spokeswoman Ana Maria Ramos says that 200 other monkeys captured in recent months have been relocated to the Caribbean Primate Research Center at the University of Puerto Rico and to other countries.

Citing a statement from Fish and Wildlife Department Director Miguel Garcia, Ramos said Friday that most of those killed were patas monkeys, while those sent to the primate center were rhesus monkeys, which are used for scientific research. Garcia said the monkeys were killed in a humane way, but did not elaborate.

Contrary to a widely held scientific theory that the mammalian Y chromosome is slowly decaying or stagnating, new evidence suggests that in fact the Y is actually evolving quite rapidly through continuous, wholesale renovation.

By conducting the first comprehensive interspecies comparison of Y chromosomes, Whitehead Institute researchers have found considerable differences in the genetic sequences of the human and chimpanzee Ys -- an indication that these chromosomes have evolved more quickly than the rest of their respective genomes over the 6 million years since they emerged from a common ancestor. The findings are published online this week in the journal Nature.

"The region of the Y that is evolving the fastest is the part that plays a role in sperm production," say Jennifer Hughes, first author on the Nature paper and a postdoctoral researcher in Whitehead Institute Director David Page's lab. "The rest of the Y is evolving more like the rest of the genome, only a little bit faster."

The chimp Y chromosome is only the second Y chromosome to be comprehensively sequenced. The original chimp genome sequencing completed in 2005 largely excluded the Y chromosome because its hundreds of repetitive sections typically confound standard sequencing techniques. Working closely with the Genome Center at Washington University, the Page lab managed to painstakingly sequence the chimp Y chromosome, allowing for comparison with the human Y, which the Page lab and the Genome Center at Washington University had sequenced successfully back in 2003.

The results overturned the expectation that the chimp and human Y chromosomes would be highly similar. Instead, they differ remarkably in their structure and gene content. The chimp Y, for example, has lost one third to one half of the human Y chromosome genes--a significant change in a relatively short period of time. Page points out that this is not all about gene decay or loss. He likens the Y chromosome changes to a home undergoing continual renovation.

"People are living in the house, but there's always some room that's being demolished and reconstructed," says Page, who is also a Howard Hughes Medical Institute investigator. "And this is not the norm for the genome as a whole."

Wes Warren, Assistant Director of the Washington University Genome Center, agrees. "This work clearly shows that the Y is pretty ingenious at using different tools than the rest of the genome to maintain diversity of genes," he says. "These findings demonstrate that our knowledge of the Y chromosome is still advancing."

Thursday, January 07, 2010

An animal testing company has paid a $4,500 fine for killing a primate by leaving it in a cage before sending it through a cage cleaner last April in Reno, the U.S. Department of Agriculture said Wednesday.

The amount for the macaque death killed at the Charles River Laboratories facility on Longley Lane facility is about half the $10,000 it paid the USDA after a May 28, 2008, incident in which severe heat led to the deaths of 32 primates in the company's lab on Dunn Circle in Sparks.

Dave Sacks, spokesman for the USDA Animal and Plant Health Inspection Service, said no information was available on how the USDA determined the fine amount.

Amy Cianciaruso, associate director of public relations for Charles River, acknowledged Tuesday the laboratory had been fined for the incident last year but said she did not know the amount.

The incident was documented in a June inspection of the facility by the USDA and brought to light Tuesday by the animal advocacy group Stop Animal Exploitation Now!

The group charged commercial cage washers "sterilize the enclosures, meaning that this primate was literally boiled alive."

Cianciaruso acknowledged the macque died as a result of being put through the cage washer, but the specific cause of death was not determined.

"This unfortunate incident was the result of human error," Charles River said in a statement. "We have enhanced our quality control processes at the Reno facility and have implemented these best practices at all of our sites globally. We expect these actions will preclude the recurrence of a similar event."

The USDA report said Charles River workers twice signed off that there were no animals in the cage. They were supposed to check before a pre-cleaning and before putting the cage into the washer, the USDA report said.

"Since an animal died, the training was not of sufficient frequency to remind the people to thoroughly look for animals before having the cages washed," the report said. "This is important for the health and safety of all the animals."

The company said several human errors led to the animal's death. As a result of the laboratory's investigation, five additional preventive measures were added to the standard operating procedures to enhance communication among workers during the cage changeover. Cameras in the dirty cage staging area were added and practices were updated at all Charles River sites, the company said.

"Providing humane and high quality care is a priority for Charles River," the company statement said. "Our work is an essential component of the research that has led to new discoveries and has played a vital role in countless medical advances for humans as well as animals."

Wednesday, January 06, 2010

Chimps have been reported dancing in rainstorms – and now it seems our closest relation has a "fire dance", too. A dominant male chimp performed such a dance in the face of a raging savannah fire in Senegal.

Anthropologist Jill Pruetz of Iowa State University in Ames recounts that the male faced the fire with "a really exaggerated slow-motion display" before redirecting his display at chimps sheltering in a nearby baobab tree. Barking vocalisations from the male, never heard in more than 2000 hours of monitoring the group, were also heard.

Pruetz and co-author Thomas LaDuke at the East Stroudsburg University of Pennsylvania suggest that the chimps were cognisant enough to predict the fire's movement, retreating short distances at a time while staying calm. Other animals, in contrast, panic when fire approaches.

"If chimps with their small brain size can conceptually deal with fire, then maybe we should rethink some of the earliest evidence for fire usage," Pruetz says. The earliest confirmed evidence of controlled fire use dates to several thousand years ago but some palaeoanthropologists argue control began as far back as 1 to 2 million years ago. The chimps' responses to two fires – set for land clearance – were seen in 2006.

Lava flowing from a volcano in the Democratic Republic of Congo is threatening a population of endangered chimpanzees.

Mount Nyamulagira erupted in the early hours of Saturday morning, raining molten rock down on the forest slopes north of the country's eastern city of Goma.

The affected area is deep inside the Virunga National Park, home to a spectacular range of mega fauna including rare chimpanzees, the okapi, and critically endangered mountain gorillas.

Rivers of lava flowing since the eruption appear likely to stop short of the nearest human settlement in Saki, according to park officials, but the eruption has been "very destructive" to the chimpanzee range on the western slope of the vast Nyamulagira volcano.

"It's chimp habitat so it will have an impact," Virunga park director, Emmanuel de Merode, said by telephone from the Congo yesterday.

"The population there was already heavily depleted by years of fighting."

The so-called "Tonga group" of chimps most directly affected by the eruption is estimated to have been reduced to as few as 40 animals prior to the latest threat.

There's an unseasonable chill in the air in the land of swim suits, sun tan lotion, golden beaches and warm balmy weather.

Temperatures across South Florida dipped in the low to mid 40s early Tuesday morning and colder temperatures, possibly near the freezing mark, are forecast for early Wednesday morning.

To keep warm residents and visitors alike are donning jackets, cranking up heaters in cars and homes and throwing an extra blanket on the bed at night.

Extra blankets also came in handy at Miami's Metrozoo where some of the animals, who are very used to our usually warm weather, got quite a shock from the chill. Metrozoo's Ron Magill said Ben, an 8-year-old chimpanzee, wasn't quite sure what to do with his burlap blanket at first. Initially he wrapped it around himself as a scarf. When he realized it wasn't doing anything to keep him warm he opened it up into a blanket, and put it over his head and then the rest of his body.

Tuesday, January 05, 2010

Zoo workers gave primates a smorgasbord of sweet treats for a Christmas treat this week.

What do you get a caged primate for Christmas? Well, take oranges off the list, at least for one chimp at Tampa's Lowry Park zoo.

Zoo workers gave primates a smorgasbord of sweet treats for a Christmas treat this week. Seconds after the zoo attendants dumped oranges into the primate habitat, a chimp grabbed one of the oranges and tossed it into the crowd of onlookers.

The orange hit a little girl in the head who had been watching. Zoo employees rushed to help the girl and called for an ice pack. But the child seemed more stunned than injured, and even stayed at the zoo after getting hit.

A judge has barred construction of a monkey-breeding facility in southern Puerto Rico that has pitted people seeking an economic lifeline for their poor mountain town against other residents and animal activists.

The decision came in a lawsuit filed by nine residents of Guayama and the People for Ethical Treatment of Animals. They argued Bioculture Ltd., the company planning the facility, failed to hold public hearings or submit a full environmental impact statement. Bioculture denied the allegations.

''We're not resting on our laurels,'' PETA spokesman Justin Goodman said Wednesday. ''If Bioculture attempts to pursue this project any further, we are poised for action.''

Bioculture will appeal the ruling by next week, lawyer Jorge Martinez Luciano said. He represents the Mauritius-based company seeking to build a facility that would hold at least 3,000 macaque monkeys and supply them to pharmaceutical companies for research.

Superior Court Judge Juan Frau Escudero ruled that construction permits should not have been awarded because the facility would be built on land reserved for agricultural purposes.

''The monkeys are not being bred for consumption of their meat,'' the judge wrote in the 16-page ruling, which was issued last week but not made public until Wednesday.

Martinez dismissed the judge's definition of what qualifies as agricultural use, and he dismissed complaints by the townspeople involved in the lawsuit.

''None of them showed ... they would suffer real and palpable damage,'' he said.

Testing hair from Asian monkeys living close to people may provide early warnings of toxic threats to humans and wildlife, according to a study published online this week in the American Journal of Physical Anthropology.

In parts of South and Southeast Asia, macaques and people are synanthropic, which means they share the same ecological niche. They drink from identical water sources, breathe the same air, share food sources, and play on the same ground.

"Macaques are similar to humans anatomically, physiologically and behaviorally," said the senior author on the study, Dr. Lisa Jones-Engel, a senior research scientist at the National Primate Research Center at the University of Washington in Seattle.

"They are also similar in their response to toxic exposures," said lead author Dr. Gregory Engel, a physician at Swedish Cherry Hill Family Medicine in Seattle and a research scientist at the UW National Primate Research Center. When macaques live in environments polluted by motor vehicles, openly disposed garbage, and industrial waste, they can come into contact with toxic substances such as lead, just as their human neighbors might.

Lead toxicity, the authors noted, remains a significant public health problem around the world. Intense exposure to lead can damage the nervous, circulatory, and reproductive systems, as well as the kidneys and liver. Exposure during childhood, according to other studies, may cause more subtle effects, such as decreased intelligence.